I found a dealer (8 deck game) who checks the hole card both legnth-wise and width-wise whenever the upcard is a ten or ace. Once I realized he was doing this every time, I started leaning over the table and looking at the mirror when he would check to see if he had a ten-valued card under his ten. To be clear- if the dealer had a ten valued card under his up ten valued card he wouldn't announce anything- he would just go the first base player to get a hand signal as a regular dealer would- I was the only one at the table leaning over, and looking at the mirror with him (the dealer didn't notice- he would be looking down at the mirror and not at me).

A couple of times I definitely was able to see paint, and decided not to split eights on one occasion (against what I knew was a dealer twenty), decided to hit a hard 17 on a couple of occasions (didn't win the hand either time), and if I didn't see any paint, I would stand on my stiff totals (since there is a 5/8 chance the dealer has a 12 - 16 and will have to hit).

A couple of questions-
1) I assume I should stay with a hard 12 (or 13+) against a dealer ten, if I know for sure that the dealer does not have a T, J, Q, K, or A underneath, but would like someone to confirm. Should I also double down with my two card hard 9 or 8 against a T with a 2 - 9 underneath his T?

2) Is this the type of thing that I can get in real trouble for doing? Would anyone try to bring criminal charges against me if I am caught leaning over the table to look at the mirror along with the dealer when he checks what his hole-card is? I recall someone once getting in trouble for trying to look at other cards in the deck when applying the yellow cut card to an 8 deck shoe.

Thanks!